Burglar-alarm.



PATENTED FEB. 21, 1905.

G. R. BOOTH.

BURGLAR ALARM.

APPLICATION FILED SEPT. 20. 1904.

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Patented February 21, 1905.

PATENT OFFICE.

GLEN RUSSELL BOOTH, OF BATAVIA, ILLINOIS.

BURGLAR-ALARIVI.

SPECIFICATION forming part of Letters Patent No. 783,014, dated February 21, 1905.

.Application filed September 20,1904. Serial No. 225,283.

To all whom it may concern:

Be it known that I, GLEN R-UssnLL Boo'rH, a citizen of the United States, residing at Batavia, in the county of Kane and State of Illinois, have invented new and useful Improvements in Burglar-Alarms, of which the following is a specification.

This invention is an electric burglar-alarm employing the closed-circuit system in the signal-circuit, and it is characterized particularly by improvements with respect to the device placed on windows, by the operation of which the circuit is broken and the alarm sounded.

The invention is illustrated in the accompanying drawing, which is a view in diagram and perspective.

Referring specifically to the drawing, the battery of the local bell-circuit is indicated at 6, the bell at 7, and the wires at 8, connected, respectively, to the armature 9 and contactpost 10 of the relay. The coils 11 of the relay are in the primary or signal circuit, the wiring of which is indicated at 12.

The window device consists of a block 14, secured to one sash and carrying copper spring-strips 15,connected,respectively, to the wires 12. Acleat 16 holds these copper strips in position, and their ends are arranged to contact with a copper or conducting plate 17, secured to the other sash. There may be two or more of these plates disposed along the sash, so that, if and when desired, the window can be left partly open for the purpose of ventilation. WVhen the copper strips are in contact with the plates 17, the circuit is closed and the magnet 11 holds the armature 9 out of contact with the post 10. If either sash be moved, the circuit is opened and the force of the spring 9 in the relay closes the contacts of the local circuit and sounds the bell in an obvious manner. A post 10, havingan insulating-point 10 acts as a stop to the armature 9 to prevent a circuit being conducted when the relay is closed.

The door arrangement includes panel-wiring, as indicated at 12*, to prevent a hole being made through the door without breaking the circuit.

It is desirable, to save the battery and for other reasons, that the primary or signal circuit be open during the day or otherwise when the protection is not needed. To this end a lock arrangement for the door is provided, as follows: One side of the circuit is connected to the look, as at 18. The other side is connected to a spring-tongue 19, located behind the bolt-hole of the socket-plate 20 in position to be struck by the bolt when the door is locked. Obviously when the door is unlocked the circuit will be broken and the system will be inactive, the local bell-circuit being opened by switch, as at 8. hen the door is locked for the night or otherwise, the local circuit is cut in by the switch 8 and the primary or signal circuit is closed by the bolt of the lock contacting with the tongue 19. If

now the bell rings, it will be known that I/Vhat I claim as new, and desire to secure by Letters Patent, is-

In a burglar-alarm for windows, the combination with two spring-strips connected to opposite sides of the line and attached to one sash, of conducting cross-bars attached to the other sash and arranged to respectively contact with the strips, in different positions of the sash.

In testimony whereof I have signed my name to this specification in the presence of two sul scribing witnesses.

GLEN RUSSELL BOOTH.

Witnesses:

PHILIP T. JUDD, I/VILLIAM W use 

